Abstract
Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar PCBs (Co-PCBs) concentrations in cormorant eggs collected from two colonies in Japan were compared. Among PCDD/Fs, the 2,3,7,8-substituted congeners dominated approximately about 90% of the total concentrations in both colonies. Concentrations of PCDD/Fs found in eggs collected from Tokyo area (average concentration=1900pg·g-1 fat) were significantly greater than the eggs from Aomori (1000pg·g-1 fat). PCDFs were found at higher level in eggs from Tokyo. In addition, Co-PCBs in egg from Tokyo were also higher (9300ng·g-1 fat) than in eggs from Aomori (2800ng·g-1 fat). Besides, toxic equivalents (TEQ) of PCDD/Fs and Co-PCBs in eggs were higher by 2.1 fold at Tokyo (3600pgTEQ·g-1 fat) than Aomori (1700pgTEQ·g-1 fat). The main contributors to the toxicity were 1,2,3,7,8-PeCDD (8, 15%), 2,3,4,7,8-PeCDF (14, 11%), CB81 (15, 11%), CB77 (17, 14%), CB126 (36, 39%) in both locations (Tokyo and Aomori), respectively.
